Means adjusting cylinders in printing press



Aug. 23, 1960 J. G. GHORMLEY, JR., ET AL 2,949,851

MEANS ADJUSTING CYLINDERS IN PRINTING PRESS Filed March 550, 1959 1N VF NTORS A TTORIVE Y Utilitfi MEANS ADJUSTING CYLINDERS IN PRINTING PRESS Filed Mar. '30, 1959, Ser. No. 802,711

Claims. (Cl. 101248) This invention relates to rotary presses of the type utilizing an intermediate cylinder to receive a printed impression from an inked plate and to transfer that impression to paper stock. The invention has reference to means and mechanism for adjusting the location of a printed impression upon such an intermediate cylinder while a press is in operation.

In high speed printing operations where printed matter is simultaneously impressed upon opposite sides of a continuous roll of newsprint or other paper stock, and especially where multistage printing involving the superimposition for-several colored impressions is necessary, the quality as well as the speed of the work is in part dependent upon the facility with which images on both sides of the paper may be kept in register without frequent stoppages and laborious adjustment of the several plates. While spacing rollers may be used with conventional presses to maintain alignment between images of successive printing stages on one side of the paper stock, compensation for lack of registry at opposite sides of the printing stock in successive printing stages has heretofore presented a more difiicult problem. Even assuming that perfect registry of all plates has been madeinitially in a photolithographic printing process, extended operation of printing equipment at high speed can cause a photolithographic plate to advance slightly in its attachment to a plate cylinder and to thus cause its impression to become slightly out of register with the impressions made by the other plates. Such slight displacement can have a great effect upon the quality of the finished work and can impose a limiting factor upon either the speed or quality of the work done. To stop the operation for adjustment of the plate upon the cylinder in such a case works to defeat the very purpose of high speed printing equipment and to let the error continue is to limit the type and quality of work which may be expected from the equipment.

Even in single stage printing where opposite sides of paper stock are printed simultaneously, the ability to adjust the upper and lower impressions relative to one another represents an economic advantage for subsequent trimming and binding operations.

Accordingly, an object of the present invention is to provide means for adjusting the relative positions of impressions at opposite sides of paper stock during a printing operation.

Another object of the invention is to provide means of rotating a cylinder carrying a printing plate relative to an impression receiving cylinder during the course of a printing operation.

A further object of the invention is to provide means for changing the position of a printed impression upon an impression receiving cylinder during a printing operation without changing the position of the cylinder itself relative to paper stock which receives the inked impression'from the cylinder.

Another object of the present invention is to provide means for changing the relative positions of impressions upon coacting impression rollers between which both tent Q "ice sides of paper stock are printed without changing the relative positions or angular velocities of the coacting impression rollers themselves.

A still further object of the invention is to provide a drive mechanism for the cylinders and rollers of a rotary printing press wherein the angular velocity of one plate carrying cylinder may be altered temporarily without altering angular velocities of otherrollers and cylinders relative to one another.

An additional object of the present invention is to provide a drive mechanism for rollers and cylinders of a printing press which permits adjustment of the position of a printed image relative to printing stock during a printing operation and which mechanism is simple to operate and is easily accessible for maintenance and repair.

These and other objects will become apparent from the following description and the accompanying drawing wherein:

Figure 1 is a schematic elevational View of printing elements of the invention shown with the outer mounting plate and the drive mechanism removed,

Figure 2 is an elevational view, similar to Figure 1, of the drive and adjustment mechanism of the invention.

Figure 3 is an enlarged elevational view of the adjustment mechanism shown in Figure 2.

Figure4 is a sectional and elevational view of the adjustment mechanism of the invention taken at a right angle with respect to Figure 3.

Figure 5 is an enlarged elevational and sectional view showing details of construction of the adjustment link mechanism illustrated in Figure 2.

In the drawings, a plate cylinder 10 adapted to receive and carry a photolithographic plate on its peripheral surface is disposed with its axis of rotation in a substantially horizontal position. Means for detaching and securing photolithographic plates to cylindrical members are well known in the printing art and a number of suitable attaching devices are commercially available and the choice of such means (not shown) is optional in the present invention. The plate cylinder 10 is provided with a coaxial shaft 11 having opposite ends extending beyond corresponding ends of the plate cylinder. One end of the shaft 11 of the plate cylinder 10 is journaled to an inner mounting plate 12 (Figure 1) and the other end of the shaft 11 is journaled to an outer mounting plate 13 (Figure 2). The inner and outer mounting plates 12 and 13 are spaced from one another and comprise vertical parallel side walls of a housing 14 which, in the illustrated embodiment ofthe inven tion, is of asymmetrical construction having one of its upper edges 15 truncated. The perimeter of each of the inner and outer mounting plates 12 and 13 is secured to and contiguous with the housing 14 so that one upper corner 15 of each mounting plate is likewise trun cated. For purposes of identification, that vertical side of the housing in juncture with the truncation 15 will be designated as the forward side of the housing 14, whereas the opposite side of the housing will be referred to as the rearward side thereof. That end of the shaft 11 of the plate cylinder 10 journaled to the outer mounting plate 13 passes through the mounting plate 13 and projects exteriorly thereof. A sprocket 16 positioned exteriorly of the outer mounting plate 13 and spaced therefrom is attached to that portion of the shaft 11 projecting exteriorly of the outer mounting plate 13. The diameter of the sprocket 16 is less than the diameter of the plate cylinder 10. Inking rollers 17 and 18 are spaced from one another and are positioned above the plate cylinder 10 so that the cylindrical surface of each of ,the inking rollers 17 and 18 is in continuous contact '17 and 18.

with the photolithographic plate carried on the cylindrical surface of the plate roller and the respective axes of the inking rollers 17 and 18 are parallel with one another and with the axis of the plate cylinder. Each of the inking rollers is provided with a coaxial shaft (not shown) constructed integrally therewith and opposite ends of each shaft ,are journaled respectively to the inner and outer mounting plates 12 and 13. A primary ink distribution roller 19 is positioned above the inking rollers 17 and 18 with its axis of rotation likewise parallel with the axis of rotation of the .plate 'less than the diameter of the primary ink distribution roller 19 and the ratio of these two diameters corresponds to the ratio which the diameter of the sprocket '16 secured to the shaft of the plate cylinder 10 bears to the plate cylinder 16 itself. A primary ink communication roller 22 is disposed with its axis of rotation parallel to the axis of rotation of the plate cylinder 10, and is positioned with its said axis at a level higher than the axis of the primary ink distribution roller 19 and rearwardly thereof with reference to the forward and rearward designations of the housing 14. The cylindrical surfaces of the primary ink communication roller 22 is in continuous contact with the cylindrical surface of the primary ink distribution roller 19. A coaxial shaft (not shown) of the primary ink communication roller 22 is journaled at its opposite ends to the inner and outer mounting plates 12 and 13, respectively. A secondary ink distribution roller 23 of substantially identical dimensions and disposition to the primary ink distribution roller 19 is spaced rearwardly thereof with its peripheral surface in continuous contact with the cylindrical surface of the primary ink communication roller 22. The secondary ink distribution roller 23 is likewise provided with a coaxial shaft 24 which is pivotally supported at its opposite ends by the inner and outer mounting plates 12 and 13. That end of the shaft 24 of the secondary ink distribution roller 23 which is pivotally supported by the outer mounting plate 13 extends through that mounting plate and projects exteriorly thereof. A sprocket 25 adapted to engage the shaft 24 and carry it in rotary motion is fitted to the shaft 24 exteriorly of the outer mounting plate 13 and the effec tive diameter of this sprocket 25 corresponds dimensionally to the diameter of the sprocket 21 fitted to the shaft of the primary ink distribution roller 19. A secondary ink communication roller 26 is positioned with its axis of rotation in horizontal alignment with the axis of rotation of the primary ink communication roller 22 but is spaced rearwardly therefrom and is spaced upwardly and rearwardly from the axis of rotation of the secondary ink distribution roller 23 so that its circumferential surface makes continuous contact with the peripheral surface of the secondary ink distribution roller 23. The secondary ink communication roller 26 is also provided with an integral and coaxial shaft (not shown) journaled at its opposite ends to the respective inner and outer mounting plates 12 and 13. An ink fountain comprising the usual fountain plate 27 and fountain roller 28 is spaced from the secondary ink communication roller 26 and is positioned rearwardly thereof so that the fountain roller 28 is situated forwardly of the fountain plate 27 with the axis of rotation of the ink fountain roller 28 parallel to the axis of rotation of the plate cylinder 10. Between the secondary ink communication 4 roller 26 and the ink fountain roller 28 a ductor roller 29 is swingably mounted so that its cylindrical surface may be put in alternate communication with the cylindrical surface of the secondary ink communication roller 26 or with the cylindrical surface of the ink fountain roller 28. As shown in Figure 1, the ductor roller 29 is in communication with the secondary inkcommunication roller 26 and its alternate position is indicated by dotted lines.

A moisture roller 30 having its axis of rotation par- 'allel with the axis of rotation of the plate cylinder 10 is positioned rearwardly thereof with its cylindrical surface in continuous contact with the pho-tolithographic plate carried by the plate cylinder 10. At its opposite ends, the moisture roller 30 is journaled to the inner and outer mounting plates 12 and 13 respectively. A water distribution roller 31 of cylindrical construction is provided with an integral and coaxial shaft 32 and is disposed with its axis parallel to the axis of the moisture roller 30 and is positioned rearwardly thereof with its peripheral surface in continuous contact with the cylindrical surface of the moisture roller 30. The shaft 32 of the water distribution roller 31 is pivotally supported by the inner and outer mounting plates 12 and 13 and that end of the shaft 32 supported by the outer mounting plate 13 extends therethrough and projects .exteriorly of the outer mounting plate 13. A sprocket 33 adapted'to be received by the shaft 32 of the water distribution roller 31 and to engage the same for rotary motion is fitted to the shaft 32 exteriorly of the outer mounting plate 13. The sprocket 33 is smaller in diameter than the roller 31 and the ratio between the diameter of the sprocket 33 and the diameter of the water distribution roller 31 is the same as the ratio between the diameter of the sprocket 16 coactively attached to the plate cylinder 10 and the diameter of the plate cylinder 10 itself. A water pan 34 is positioned rearwardly of the water distribution roller 31 and is spaced therefrom. A pan roller 35 is positioned above the water pan 34 so that its peripheral surfaces and those of its coaxial shaft 36 are at all points spaced above the surfaces of the pan but so that a lower portion of the pan roller 35 is immersed in plate rnoistening fluid contained in the water pan 34. Opposite ends of the shaft 36 of the pan roller 35 are journaled to the inner and outer mounting plates 12 and 13 respectively. A water ductor roller 37 is positioned between the pan roller 35 and the water distribution roller 31 and is there swingably mounted by means well known in the printing art to alternately communicate with the water distribution roller 31 (as shown in Figure 1) or with the pan roller 35 (as indicated schematically in Figure 1).

A lower plate cylinder 38 of substantially identical construction and dimensions with the plate cylinder 10, previously described, is positioned therebeneath and is spaced therefrom in a disposition such that its axis of rotation is parallel to the axis of rotation of the plate cylinder 10. The lower plate cylinder 38 is secured to a shaft 39 coaxial therewith and the shaft 39 is journaled to the inner and outer mounting plates 12 and 13 respectively, and one end of the shaft 39 extends through and projects exteriorly of the outer mounting plate 13. A sprocket 40, identical in efiective diameter to the sprocket 16 secured to the shaft 11 of the plate cylinder 10, is secured to that portion of the shaft 39 projecting exteriorly of the outer mounting plate 13.

The lower plate cylinder 38 coacts and communicates with a train of ink transporting rollers and with a train of moisture carrying rollers, which trains of rollers are equivalent in arrangement and function to the trains of described rollers coacting and communicating with the plate cylinder 10. Since the equivalence will be apparent to those skilled in the art, equivalent members with corresponding construction and arrangement are identi roller 26a, a lower fountain plate 27a, a lower fountain roller 28a, and a lower ink ductor roller 29a coact to transport ink to the photolithographic plate carried by the lower plate cylinder 38 in the same way as their numerical counterparts transport ink to the plate carried by the plate cylinder 10. In like manner, a lower moisture roller 30a, lower water distribution roller 31a, lower pan 34a, lower pan roller 35a and lower water ductor 37a cooperate to carry moisture to the photolithographic plate carried by the lower plate cylinder 38. Sprockets 21a, 25a and 33a are also constructed and arranged in accordance with their numerical counterparts. It will be noted that the physical arrangement of these components associated with the lower plate cylinder 38 is substantially a mirror image of the arrangement of equivalent components associated with the plate cylinder 16.

An impression cylinder 41 having a coaxial shaft '42 is adjacently positioned forwardly of and beneath the plate cylinder 10. The peripheral surface of the impression cylinder 41 carries a rubber blanket which may be integrally constructed with the impression cylinder 41 or which may be detachably secured thereto as is known in the art. The diameter of the impression cylinder 41 as measured to include the blanket coextensive with its cylindrical surface is substantially identical to the diameter of the plate cylinder 16 as measured to include the photolithographic plate carried at its periphery. The shaft 42 of the impression cylinder 41 is journaled at its opposite ends to the mounting plates 12 and 13 and one end of the shaft 42 extends through the outer mounting plate 13 and projects exteriorly thereof. A sprocket 43, identical in its efiective diameter to the sprocket 16 attached to the shaft 11 of the plate cylinder 10, is secured to the shaft 42 of the impression cylinder 41 exteriorly of the outer mounting plate 13. A lower impression cylinder 44 of construction identical to that of the impression cylinder 41 is mounted therebeneath and is so positioned that the outer surface of the rubber blanket it carries is in continuous contact with the photolithographic plate carried by the lower plate cylinder 38 and is also in proximate contact with the rubber blanket carried by the impression cylinder 41. A shaft 45 coaxial with the lower impression cylinder 44 and secured thereto is journaled at its opposite ends to the inner and outer mounting plates 12 and 13 respectively and one end of the shaft 45 extends through and projects exteriorly of the outer mounting plate 13. A sprocket 46 having an efiective diameter equal to the diameter of the sprocket 43 associated with the impression cylinder 41 is secured to the shaft 45 of the lower impression cylinder 44 exteriorly of the outer mounting plate 13.

Paper stock 47 is conducted by a rear web roller 48 through an opening in the rearward wall of the housing 14 to a course between the impression cylinders 41 and 44 whereby the upper surface of the paper stock is in contact with the rubber blanket carried by the impression cylinder 41 and the lower surface of the paper stock is in contact with the rubber blanket carried by the lower impression cylinder 44. The paper stock 47 travels through the housing 14 in a forwardly direction as indicated by the adjacent arrow in Figure 1 and is conducted out of the housing 14 through an opening in the forward wall thereof by a forward web roller 49 exteriorly positioned with respect to the housing. A spacing roller 50 is swingably and adjustably mounted with respect to the forward web roller 49.

A bell crank 51 having upper and lower radially extending arms52 and 53 which are substantially flat and coplanar and which form an obtuse angle with one an other is provided with a journal box 54 at the juncture of the arms 52 and 53. The journal box 54 is disposed to receive a pivot bolt 55 with its principal axis perpendicular to the primary plane of the radial arms 52 and 53. On one side of the bell crank 51 adjacent the journal box 54 an annular collar 56 is formed as an integral part thereof so that the projecting edge of the collar 56 is spaced from but parallel with the proximate surface of the bell crank 51 and so that a circular opening through the annular collar 56 forms a continuation of the journal box 54. At the extended end of the upper radial arm 52 of the bell crank 51 and at the surface thereof opposite the collar 56 a stub shaft 57 is secured and projects outwardly therefrom in a disposition perpendicular to the principal plane of the bell crank 51. A sprocket 58 is journaled to the stub shaft 57. At the extended end of the lower radial arm 53 of the bell crank 51 a stub shaft 59 is secured to the surface opposite the collar 56 and projects therefrom with its axis parallel to the axis of the stub shaft 57 secured to the other radial arm of the bell crank 51. A sprocket 60 is journaled to the stub shaft 59 secured to the lower radial arm 53 of the bell crank 51. The bell crank 51 is pivotally mounted to the outer surface of the outer mounting plate '13 at a position beneath and rearwardly of the sprocket 16 attached to the-shaft 11 of the plate cylinder 10 by the pivot bolt 55 positioned with the journal box '54. A nut 61 engages the pivot bolt 55 interior-1y of the outer mounting plate 13. Anear 62 formed as a rearward extension of the upper radial arm 52 of the bell crank 51 and located thereon near the stub shaft 57 projects rearwardly thereof in the plane of the upper and lower radial arms 52 and 53; an opening is provided through the ear 62. An adjustment link 63 comprising a rod planed atone of its ends 64 and provided with threads 65 at its opposite end and having a cylindrical shank 66 therebetween is provided with an opening through its planed end 64. A wrist pin 67 extending through the opening in the planed end 64 of the adjustment link 63 and through-the opening in the ear 62 of the bell crank 51 is there secured by a nut 68.

An adjustment knob 69, comprising a cylindrical member having a flanged section 70 provided with knurling about its outer perimeter, a central section 71 smaller in diameter than the flanged section 70 but coaxial therewith, and a sleeve section 72 smaller in diameter than the central section 71 but also coaxial therewith is provided with a threaded opening 73 extending continuously through the flanged, central, and sleeve sections 70, 71 and 72, of the adjustment knob 69 in axial alignment with the common axis thereof. The threaded opening 73 is adapted to receive the threaded end of the adjustment link 63 and to engage its threads 65. The sleeve section 72 of the adjustment knob 69 is fitted through an opening in the rearward vertical wall of the housing 14 so that the central and flanged portion 71 and 70 of the adjustment knob 69 project exteriorly thereof. A grommet 74 engages the outer surface of the sleeve section 72 of the adjustment knob 69 at a position adjacent the interior of the rearward vertical wall of the housing 14. A check nut 75 provided with a set screw 76 engages the threads 65 of the adjustment link 63 forwardly of the grommet 74. An L-shaped limiting bracket 77 is attached to the interior surface of the rear vertical wall of the housing -14 and projects forwardly therefrom to a point spaced from the grommet 74. A stop 78 forming the inner termination of the limiting bracket '77 extends to the immediate proximity of the link 63.

A drive shaft 79 is journaled to the outer mounting plate 13 near the bottom of the forward wall of the housing 14 (Figure 2) and projects exteriorly thereof with its axis parallel to the axis of the plate roller 10.

power transmission means may be used for purposes of syncronization where more than one press is utilized ina particular printing operation. Teeth of the drive sprocket 80 engage a continuous sprocket chain 81 which is conducted by an idler 82 and a plurality of guide sprockets to-engagement with the sprockets previously described.

Tracing the course of the sprocket chain 81 in a generally counterclockwise direction as indicated by ad jacent arrows in Figure 2, it is seen that the sprocket chain 81 extends rearwardly from engagement with teeth on the lower side of the drive sprocket St 'to engagement with teeth on the lower periphery of a reduction idler sprocket 82 rotatably attached to and spaced from the exterior surface of the outer mounting plate 13 by a shaft 83 positioned on the outer mounting plate 13 near the bottom of the rearward wall of the housing 14. The sprocket chain M is conducted upwardly from the reduction idler sprocket 82 by the rearward teeth of a first guide sprocket 8d rotatably secured to the outer mounting plate 13 exteriorly thereof and at a position thereon in approximate vertical alignment with the reduction idler 8'2 but at a level lower than the sprocket 25a attached to the shaft 24a of the lower secondary ink distribution roller 23a. rom the first guide sprocket 84 the sprocket chain runs to engagement with teeth on the lower periphery of the sprocket 2541 which carries the shaft 24a of the lower secondary ink distribution roller 23a and thence upwardly around that sprocket 25a to engagement with teeth on the forward periphery of the sprocket 33a adapted to carry the water distribution roller 31a. A second guide sprocket -85 rotatably secured to the outer mounting plate 13 and positioned exteriorly thereof conducts the sprocket chain 81 rearwardly and thence upwardly and forwardly to engagement with teeth at the forward periphery of a third guide sprocket 86 rotatably mounted to the exterior surface of the outer mounting plate 13 and positioned thereon beneath and slightly rearwardly of the pivot bolt 55 of the bell crank 51 from which the third guide sprocket 86 is spaced. The sprocket chain 8 1 extends from the third guide sprocket do to engagement with teeth at the rearward periphery of the sprocket 33 adapted to carry the upper water distribution roller 31 and thence to teeth at the rearward periphery of the sprocket 25 fitted to engage the shaft 24 of the secondary ink distribution roller 23; and thence the sprocket chain 81 runs forwardly to engagement with teeth on the upper periphery of the sprocket 21 which is adapted to carry the shaft '20 of the primary ink distribution roller 19. From the sprocket 21 associated with the primary ink distribution roller 19 the sprocket chain 81 is conducted to the upper periphery of the sprocket 58 journaled to the stub shaft 57 of the upper radial arm 52 of the bell crank 51 and thence clockwise around that sprocket to engagement with teeth on the upper periphery of the sprocket 16 secured to the shaft 1'1 of the plate cylinder and thence counterclockwise around that cylinder to engagement with rearward teeth of the sprocket 60 journaled to the stub shaft 59 of the lower radial arm 53 of the bell crank 51. Lower teeth of the sprocket 43 secured to the shaft 42 of the impression cylinder 41 conduct the sprocket chain 81 forwardly from the lower radial arm 53 of the bell crank 51 and upwardly to engagement with rearward teeth of a fourth guide sprocket 87 rotatably mounted to the exterior sur face of the outer mounting plate 13 at a position thereon forwardly of and above the sprocket 43 secured to the shaft 42 of the impression cylinder 41. From the fourth guide sprocket 87 the sprocket chain 81 proceeds downwardly to engagement with teeth on the forward periphery of the sprocket 46 "secured to the shaft 45 of tion roller 19a.

7 the lower impression cylinder 44 and is conducted thence 're'arwardly to'upper peripheral teeth of the sprocket 40 attached to the shaft-39 of the lowerplate cylinder 38. Fromengagement with rearward teeth of the sprocket 4i) coacting with the lower plate cylinder 38 the sprocket chain courses downwardly to engagement with teeth on 'the rearward periphery of the sprocket 21a adapted to' rotate the shaft 20a of the lower primary ink distribu- A fifth guide sprocket 88 positioned in approximate vertical alignment with the drive sprocket and there rotatably secured to the outer surface of the outer mounting plate 13 conducts the sprocket chain 81 from the sprocket 21a associated with the lower primary ink distribution roller 19a to the teeth on the "rearward periphery of the drive sprocket 80. A horizontally disposed tension bar 89 is pivotally connected to the'exteriorsurface of the outer mounting plate 13 by a pin 90. A spring 91 connects one end of the tension bar 89 to the base of the housing 14. A sprocket 92 is rotatably connected to the other end of the tension 'bar'89 and engages the chain 81 in its path between the drive sprocket 80 and the reduction idler 82.

As shown in Figure 2 a mechanism is provided to impart a reciprocating lateral motion to the ink and moisture distribution rollers 19, 19a, 23, 23a, 31 and 31a. A table sprocket 93 is rotatably attached to the outer surface of the outer mounting plate 13 and is positioned thereon approximately equidistantly from the forward and rear vertical walls of the housing 14 above the drive sprocket 8t) and'the reduction idler 83 but beneath the first and fifth guide sprockets 84 and 83. A lower vertical shaft 94 extends between lower and central pillow blocks 95 and 96 each being secured to the outer surface of the outer mounting plate 13 and projecting outwardly and equidistantly therefrom. The lower vertical shaft 94 is journaled to the lower and central pillow blocks 95 and 96 so that the lower vertical shaft 94 is spaced from the table sprocket 93 but is parallel with the outer surface thereof and passes through the line of the axis of rotation of the table sprocket 93. A collar 97 joins the upper end of the lower vertical shaft 94 to the lower end of an upper vertical shaft 98 (shown in fragment) ly thereof. Opposite ends of the upper rocker am 100 respectively engage outwardly extending ends of the shafts 29 and 24 of the primary and secondary ink distribution rollers 19 and 23. A lower rocker arm 101 is secured to the lower vertical shaft 94 and projects forwardly and rearwardly thereof with opposite ends of the lower rocker arm engaging outwardly extending ends of the shafts 20a and 24a of the lower primary and secondary ink distribution rollers 19a and 23a. A lower walking beam 102 is pivotally connected at one of its ends to a mounting bracket 103 secured to the outer surface of the outer mounting plate 13 and engages the exteriorly projecting end of the shaft 32a of the water distribution roller 31a. A toggle arm 104 secured to the lower vertical shaft 94 engages the walking beam forwardly of the shaft 32a of the lower water distribution roller 31a. An upper walking beam 105 is pivotally connected at one of its ends to an upper mounting bracket 106 and engages the shaft 32 of the water distribution roller 31. A toggle arm 107 (shown in fragment) secured to the upper vertical shaft 98 engages the upper walking beam 105 forwardly of the shaft 32 of the water distribution roller 33. An oscillating bar 103 is pivotally connected in a vertical plane of rotation at one of its ends to the lower vertical shaft 94 and is eccentrically connected at its other end to the outer surface of the table sprocket 93 by a universal swivel coupling (not shown). A sprocket chain 109 engaging teeth 9 of the table sprocket 93 is driven by engagement with the teeth of a sprocket 110 (indicated by dotted lines in Figure 2) secured to the shaft 83 of the reduction idler 82 and the outer mounting plate 13.

In operation, rotating force from a power source (not shown) turns the drive shaft 79 which carries the sprocket 80 and which, in turn, drives the sprocket chain 81 in its described course. Driven by the sprocket chain 81 the plate cylinder 10, the water distribution roller 31, the primary ink distribution roller 19 and the sec ondary ink distribution roller 23 are given a counterclockwise rotation (with reference to the views presented in Figures 1 and 2). By frictional contact with adjacent cylindrical surfaces and fluids carried thereon the inking rollers 17 and 18, the ink communication rollers 22 and 26, and the moisture roller 30 are imparted with an opposite or clockwise rotation. The fountain roller 28 and the pan roller 35 are driven by means (not shown) independent of the drive shaft 79. The doctor rollers 29 and 37 alternately derive rotating force from contact with the rollers between which they are swingably mounted. tact between the described rollers causes ink or moisture to be carried from the fountain or pan to their peripheral surfaces by which the fluids are transported and distributed to peripheral surfaces of successive rollers. By its direction of rotation, the plate cylinder carries successive portions of the photolithographic plate attached thereto into contact with the moisture roller 30 after contact with the blanket carried by the impression cylinder 41 and before contact with the inking rollers 17 and 18. As is well known in the printing art, such contact with moisture containing suitable additives will cause selected portions of the photolithographic plate to reject the adherence of ink as those portions subsequently come into contact with the inking rollers 17 and 18. Further rotation of the plate cylinder 10 causes inked portions of the photolithographic plate carried thereby to come into contact with the rubber blanket carried by the impression cylinder 41 which is driven by the chain 81 through engagement with the impression cylinder sprocket 43 in an opposite direction of rotation to that of the plate cylinder 10. By contact with successive parts of the photolithographic plate carried by the plate cylinder 10, a printed image of the plate is impressed upon the rubber blanket carried by the impression cylinder 41 and this image is thereafter transferred to the upper surface of the paper stock 47. Identical diameters of the plate cylinder 10 and the impression cylinder 41 as well as their respective coacting sprockets 16 and 43 assure, during normal operation, that a given point on the photolithographic plate will contact the same point on the rubber blanket in successive rotations of the plate and impression cylinders 10 and 41. Hence, there is no rotation of the impression cylinder relative to the plate cylinder 10 and the angular velocities of those two cylinders 10 and 41 are the same. The direction of rotation of the lower impression cylinder 44, as imparted by the chain 81 through engagement with the lower impression cylinder sprocket 46, is opposite to that of the impression cylinder 41 so that the paper stock 47 is carried forwardly between the two. Identical dimensions of these two cylinders and of their respective sprockets 43 and 46 assure substantially identical angular velocities during a printing operation.

The plate cylinder 10 may be rotated relative to the impression cylinder 41 by hand rotation of the adjust ment knob 69. Considering all parts of the invention at rest so that the drive shaft 79 is fixed in its position, manual rotation of the adjustment knob 69 so that the threaded opening therein 73 engages more of the threads 65 of the link 63 will force the link toward the adjustment knob 69 and the link 63 through its connection Coaction of and concrank 51 about its pivot bolt 55 connection to the outer mounting plate 13 so that the upper sprocket 58 of the bell crank 51 will be carried toward the adjustment knob 69 whereas the lowersprocket 60 of the bell crank51 will be displaced forwardly and upwardly toward the forward perimeter of the plate cylinder sprocket 16. The upper bell crank sprocket 58 will carry with it a portion of the sprocket chain 81 which had previously engaged the plate cylinder sprocket 16 while the lower bell crank sprocket 60 will release a corresponding length of the chain 81. By its displacement, the sprocket chain 81 will rotate both of the bell crank sprockets 58 and 60 and the plate cylinder sprocket 16 while ,all other sprockets will remain substantially unaffected. Thus, the plate cylinder 10 may be rotated relative to the impression cylinder 41. Rotation of the adjustment knob 69 while all rollers and cylinders are in motion has the effect of temporarily altering the angular velocity of the plate cylinder 10 relative to the angular velocity of the impression cylinder 41 with the same result. The image made by the photolithographic plate carried by the plate cylinder 10 upon the rubber blanket carried by the impression cylinder 41 is displaced to a new position on the rubber blanket with a resulting change in registry between impressions printed upon the upper and lower surfaces of the paper stock 47. Because the position of the upper impression cylinder 41 relative to the lower impression cylinder 44 is not altered by the described adjustment, the paper stock passing therebetween is subjected to no stress during the adjustment. Frictional stress of the adjustment is absorbed'in the rubber blanket carried by the impression roller 41 and the resilience of that member is such that no damage is done thereby.

In series operation, where two or more presses are utilized in a single printing operation as in the printing of a multicolored image, several presses may be positioned in a line and paper stock may be continuously fed through the series. Letting Figure 1 represent the first press in sucha series and Figure 2 represent the second, paper stock 47 is positioned between the upper and lower impression cylinders 41 and 44 of the first press which cylinders simultaneously print different matter in a single color on opposite sides of the paper stock 47. Leaving the first press through the opening (not shown) in the forward wall of its housing 14, the paper stock is conducted over the forward web roller 49, under the spacing roller 50 andthence over the rearward web roller 48 (not shown in Figure 2) of the second press and between its upper and lower impression cylinders. While the presses are running the spacing roller may be adjusted so that the image on the lower surface of the printing stock as printed by the first press is in register with the image on the lower surface of the printing stock as printed by the second press. Once this initial adjustment has been made, the adjustment knob 69 of the second press may be turned and consequent rotation of the plate cylinder 10 relative to the impression cylinder 41 in the second press may be utilized to adjust the registry on the upper side of the paper stock 47 so that the image printed by the upper impression cylinder 41 in the second press will register with the matter printed by the upper impression cylinder 41 in the first press. The check nut and the limiting bracket 77 may be used to preset or secure the described adjustment.

The invention is not limited to'the exemplary construction herein shown and described but may be made in various ways within the scope of the appended claims.

What is claimed is:

1. In a printing press having an axially mounted plate cylinder carrying a photolithographic plate on the peripheral surface thereof and having an axially mounted impression cylinder provided with a blanket of rubber or equivalent material secured to its peripheral surface which blanket is in communication with said photolithographic with the ear 62 of the bell crank 51 will rotate the bell 75 plate carried by said plate cylinder, a sprocket coaxially another in a plane of rotation perpendicular to the axis 'of rotation of said plate cylinder and extending to terminations spaced from tangencies of said plate cylinder at substantially opposed peripheral surfaces thereof, a

sprocket rotatably attached to the projecting end of one of said radial members of said bell crank with the axis of rotation of said sprocket disposed parallel to the axis of rotation of said bell crank, a sprocket rotatably attached to the projecting end of the other said radial arm of said bell crank with its axis of rotation parallel to the axis of rotation of said bell crank, a sprocket chain engaging each of said sprockets with said sprocket chain extending directly from said sprocket on one of said radial arms of said bell crank to said sprocket coaxially secured to said plate cylinder and thence extending directly to said sprocket secured to the other said radial arm of said bell crank, means driving said sprocket chain, and means providing limited angular adjustment of said bell crank about its pivotal mounting.

2. The invention as defined in claim 1 and including an axially mounted second impression cylinder provided with a blanket of rubber or equivalent material secured to its peripheral surface and positioned with the peripheral surface of said rubber blanket carried by said second impression cylinder adjacent to the said blanket carried by the first said impression cylinder, an axially mounted plate cylinder carrying a photolithographic plate at its peripheral surface with said photolithographic plate in communication with said blanket carried by the second said impression cylinder, a sprocket coaxially secured to said second impression cylinder, a sprocket coaxially secured to said second plate cylinder, means conducting paper stock between the first said impression cylinder and the said second impression cylinder, and means communicating ink and moisture to the said photolithographic plates carried by the said plate cylinders.

3. The inventio'n as defined in claim 2 and wherein said means communicating ink and moisture to the said photolithographic plates carried by the said plate cylinders includes at least one axially mounted ink roller disposed with its axis of rotation parallel to the axis of rotation of said plate cylinders, a sprocket coaxially mounted to said ink roller with said sprocket engaging said chain, at least one moisture communicating roller disposed with its axis of rotation parallel to the axis of rotation of the first said plate roller, and a sprocket co- 12 axially secured to said moisture communicating roller with said sprocket engaging said sprocket chain.

'4. In a printing press, an axially mounted printing cylinder having a peripheral surface adapted to receive and carry ink on selected portions thereof, an axially mounted impression receiving cylinder provided with a resilient ink conducting peripheral surface and which peripheral surface communicates with said peripheral surface of said printing cylinder, a sprocket coaxially secured to said printing cylinder, a sprocket coaxially secured to said impression receiving cylinder, a pivotally mounted bell crank including two radial arms projecting from said pivot mounting and forming an angle with one another in a plane of rotation perpendicular to the axis of rotation of said printing cylinder and extending to terminations respectively spaced from substantially opposed peripheral surfaces of said printing cylinder, a sprocket rotatably attached to the projecting end of one arm of said bell crank, a sprocket rotatably attached to the projecting end of the other arm of said bell crank, a sprocket chain engaging each of said sprockets with said sprocket chain engaging the sprocket rotatably secured to one arm of said bell crank between the engagement of the sprocket chain with the sprocket secured to the said printing cylinder and the sprocket engaging said impression receiving cylinder, and spacing means adjustably maintaining one radial arm of said bell at a fixed distance from a stationary part of said printing press.

5. In a printing press having an axially mounted printing cylinder and an axially mounted impression roller in rotating contact therewith, a sprocket mounted on the axle of said plate cylinder, at sprocket mounted on the axle of said impression roller, a pivotally mounted bell crank, a sprocket rotatably mounted on one end of said bell crank, a sprocket rotatably mounted on the other end of said bell crank, a sprocket chain engaging each of said sprockets with said sprocket chain engaging the sprocket rotatably secured to one end of said bell crank between the engagement of said sprocket chain with said sprocket mounted on the axle of said printing cylinder and with said sprocket mounted on the axle of said impression roller, means driving said sprocket chain, and adjustable means fixing the angular position of said bell crank on its pivotal mounting.

References Cited in the file of this patent UNITED STATES PATENTS 2,229,226 Scott Jan. 21, 1941 

